Energy storage and release system for fuel production through thermochemical coupling CO2 reduction, working method and configuration method

Abstract

The invention belongs to the technical field of energy storage systems, and relates to an energy storage and release system for fuel production through thermochemical coupling CO2 reduction, a working method and a configuration method. The energy storage and release system comprises an energy storage system and an energy release system; the energy storage system comprises a photovoltaic electricity abandoning unit, a thermochemical energy storage reactor, a water electrolyser, a carbon dioxide storage tank A, a hydrogen storage tank, an oxygen storage tank, equipment for preparing methanol from carbon dioxide and a methanol storage tank; the photovoltaic electricity abandoning unit is connected with the thermochemical energy storage reactor and the water electrolyser; the thermochemical energy storage reactor is connected with the carbon dioxide storage tank A. The water electrolyser is connected with the hydrogen storage tank and the oxygen storage tank. The carbon dioxide storage tank A and the hydrogen storage tank are respectively connected with the equipment for preparing methanol from carbon dioxide; the carbon dioxide methanol preparation equipment is connected with the methanol storage tank; the energy release system comprises methanol combustion heat supply equipment, a carbon dioxide storage tank B and a thermochemical energy release reactor which are connected in sequence; and the methanol combustion heat supply equipment is respectively connected with the methanol storage tank and the oxygen storage tank. The problem that an existing energy storage system is high in cost is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage systems, and specifically relates to a thermochemically coupled CO2 reduction fuel production energy storage and release system, a working method, and a configuration method. Background Art

[0002] Calcium carbonate-calcium oxide cyclic thermochemical energy storage has the advantages of high heat storage density, long energy storage time, and low price of heat storage medium. However, since the gas involved in the reaction is carbon dioxide, additional carbon dioxide gas tanks and gas circuits need to be built, which increases the complexity of the system while also increasing investment and operating costs.

[0003] Thermochemical CO2 reduction to fuel storage is also a promising energy storage technology. However, in this energy storage solution, the CO2 is typically sourced from captured coal-fired power plants, which places certain requirements on project site selection. Using CO2 gas tanks requires purchasing the gas, increasing costs.

[0004] Therefore, a new system is urgently needed to maximize the utilization of carbon dioxide and reduce the costs of both energy storage methods. Summary of the Invention

[0005] The purpose of the present invention is to provide a thermochemically coupled CO2 reduction fuel production energy storage and release system and a working method and configuration method, which solves the problem of high cost of existing energy storage systems.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention discloses a thermochemical coupled CO2 reduction fuel production energy storage and release system, comprising an energy storage system and an energy release system;

[0008] The energy storage system includes a photovoltaic power curtailment unit, a thermochemical energy storage reactor, a water electrolyzer, a carbon dioxide storage tank A, a hydrogen storage tank, an oxygen storage tank, a carbon dioxide to methanol device, and a methanol storage tank;

[0009] The photovoltaic power abandonment unit is connected to the thermochemical energy storage reactor and the water electrolyzer to provide power to the thermochemical energy storage reactor and the water electrolyzer;

[0010] The thermochemical energy storage reactor is connected to the carbon dioxide storage tank A, and the water electrolyzer is connected to the hydrogen storage tank and the oxygen storage tank respectively; the carbon dioxide storage tank A and the hydrogen storage tank are respectively connected to the carbon dioxide to methanol equipment; the carbon dioxide to methanol equipment is connected to the methanol storage tank;

[0011] The energy release system includes a methanol combustion heating device, a carbon dioxide storage tank B and a thermochemical energy release reactor connected in sequence. The methanol combustion heating device and the thermochemical energy release reactor are used for energy release and heating;

[0012] The methanol combustion heating equipment is connected to the methanol storage tank and the oxygen storage tank respectively.

[0013] Furthermore, the thermochemical energy storage reactor is filled with calcium carbonate material, and the thermochemical energy release reactor is filled with calcium oxide material.

[0014] Furthermore, the methanol combustion heating equipment is also connected to the water electrolyzer to supply water to the water electrolyzer.

[0015] The present invention also discloses a working method of the energy storage and release system based on the thermochemically coupled CO2 reduction fuel production method, comprising the following steps:

[0016] The thermochemical energy storage reactor uses the abandoned photovoltaic power to perform energy storage reaction, generating carbon dioxide, which is stored in the carbon dioxide storage tank A;

[0017] The water electrolyzer uses the abandoned photovoltaic power to perform electrolysis reactions to generate hydrogen and oxygen, which are stored in hydrogen storage tanks and oxygen storage tanks respectively;

[0018] The carbon dioxide storage tank A and the hydrogen storage tank provide reaction gas for the carbon dioxide to methanol equipment to generate methanol, which is stored in the methanol storage tank;

[0019] The methanol storage tank and oxygen storage tank provide reaction gas for the methanol combustion heating equipment to generate carbon dioxide, which is stored in the carbon dioxide storage tank B and provides heat at the same time;

[0020] The carbon dioxide storage tank B provides reaction gas to the thermochemical energy release reactor, performs energy release reaction in the thermochemical energy release reactor, and provides heat.

[0021] Furthermore, calcium oxide is generated in the thermochemical energy storage reactor and transferred to the thermochemical energy release reactor;

[0022] Calcium carbonate is generated in the thermochemical energy release reactor and transferred to the thermochemical energy storage reactor;

[0023] During the reaction in the methanol combustion heating equipment, the generated water is circulated to the water electrolyzer.

[0024] The present invention also discloses a configuration method of the energy storage and release system based on the thermochemically coupled CO2 reduction fuel production method, which includes the following two parts:

[0025] Configure the energy storage system:

[0026] Average photovoltaic power curtailment, new heating demand load, and average outdoor daily ambient temperature established over time;

[0027] Determine the relationship between the rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer based on the energy consumption in the thermochemical energy storage reactor and the water electrolyzer;

[0028] The average daily photovoltaic power curtailment power is calculated based on the average photovoltaic power curtailment power established with time as the axis;

[0029] The rated power of the water electrolyzer and the rated power of the thermochemical energy storage reactor are obtained based on the relationship between the rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer and the average daily photovoltaic power abandonment;

[0030] Determine the storage time of the thermochemical energy storage reactor and the operating time of the electrolyzer based on the average daily photovoltaic power curtailment.

[0031] Determine the volumes of CO2 storage tanks, H2 storage tanks, O2 storage tanks, and methanol storage tanks based on the gas requirements of the thermochemical energy storage reactor and CO2 to methanol equipment;

[0032] Determine the power and operating time of the CO2-to-methanol equipment based on the energy storage time of the thermochemical energy storage reactor and the operating time of the electrolyzer;

[0033] Configure the energy release system:

[0034] Determine the total heating load of the thermochemical energy release reactor and methanol combustion heating equipment based on the average load of the new heating demand and the average daily outdoor ambient temperature;

[0035] Determine the relationship between the rated power of the thermochemical energy release reactor and the rated power of the methanol combustion heating equipment;

[0036] Based on the temporal variation of the average load of the newly increased heating demand and the principle of economic optimization, the optimal heating duration of the system is determined. Based on the optimal heating duration and heating load, the total heating power of the thermochemical energy release reactor and the methanol combustion heating equipment is calculated.

[0037] The rated power of the thermochemical energy release reactor and the rated power of the methanol combustion heating equipment are calculated based on the heating power.

[0038] Furthermore, the rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer satisfy the following relationship:

[0039] P H2 =7P r Among them, P r is the rated power of the thermochemical energy storage reactor, P H2 Rated power of the water electrolyzer.

[0040] Furthermore, the storage time of the thermochemical energy storage reactor is hc, and the operation time of the electrolyzer is h H2 ;

[0041] hc is the total time that Pq is in the range of 0.6Pt to Pt, h H2is the total time that Pq is in the range of 0.8Pt to Pt;

[0042] Pq is the average photovoltaic power curtailment power established based on time, and Pt is the average daily photovoltaic power curtailment power;

[0043] The rated power of the carbon dioxide to methanol equipment is Pf, the operating time is hf, and the calculation expression is:

[0044] hf=hc,Pf=P H2 / 3;P H2 Rated power of the water electrolyzer.

[0045] Furthermore, the rated power of the thermochemical energy release reactor is P r1 The rated power of the methanol combustion heating equipment is P m , the relationship between the two is: The redundancy

[0046] Furthermore, the total heating power of the thermochemical energy release reactor and the methanol combustion heating equipment is calculated based on the optimal heating time ho and the heating load W1, and the expression is: P1 = W1 / ho;

[0047] Among them, ho is the optimal heating time, W1 is the heating load, and P1 is the total heating power of the thermochemical energy release reactor and methanol combustion heating equipment;

[0048] The rated power P of the thermochemical energy release reactor is calculated based on the heating power P1. r1 Methanol combustion heating equipment P m , based on: P1=P r1 +P m .

[0049] Compared with the prior art, the present invention has the following beneficial technical effects:

[0050] The present invention discloses a thermochemically coupled CO2 reduction fuel production energy storage and release system, comprising an energy storage system and an energy release system. The energy storage system includes a photovoltaic power curtailment unit, a thermochemical energy storage reactor, a water electrolyzer, a carbon dioxide storage tank A, a hydrogen storage tank, an oxygen storage tank, a carbon dioxide to methanol production device, and a methanol storage tank. The energy release system includes a methanol combustion and heating device, a carbon dioxide storage tank B, and a thermochemical energy release reactor connected in sequence. The methanol combustion and heating device and the thermochemical energy release reactor are used for energy release and heating. The photovoltaic power curtailment unit converts the curtailed electricity generated by renewable energy into chemical energy for storage, thereby avoiding wasteful curtailment and improving the utilization rate of renewable energy. The thermochemical energy storage reactor carries out an energy storage reaction, and the generated carbon dioxide is piped into the carbon dioxide storage tank A for storage. The water electrolyzer drives water electrolysis to generate H2 and O2, converting the electrical energy into hydrogen energy for storage and use in subsequent energy release steps. The carbon dioxide storage tank A and the hydrogen storage tank provide reaction gases to the carbon dioxide to methanol production device, where methanol is synthesized. The generated methanol is piped into the methanol storage tank for storage. During the energy release process, the methanol storage tank and the oxygen storage tank provide reaction gas for the methanol combustion and heating equipment. Methanol is burned in the methanol combustion and heating equipment, and the generated carbon dioxide enters the carbon dioxide storage tank B through a pipeline for storage, while providing heat. The carbon dioxide storage tank B provides reaction gas for the thermochemical energy release reactor, and an energy release reaction is carried out in the thermochemical energy release reactor: CaO+CO2—CaCO3, providing heat. Based on physical characteristics and load requirements, the present invention realizes the diversification of equipment functions through the mutual coordination between equipment, makes full use of new energy waste electricity, achieves efficient energy utilization through configuration, and reduces costs; solves the problems of new energy waste electricity recovery and heating at the same time by configuring electricity storage and heating capacity; cooperates with the thermochemical heat storage and release system with methanol combustion heating, and ensures reliable heating through dual heat source complementary heating.

[0051] The present invention also provides a configuration method for the energy storage and release system. According to the gas requirements of the thermochemical reactor and the methanol production equipment, the volume of the storage tank (CO2, H2, O2, methanol) is accurately calculated to avoid the cost increase caused by excessive storage tank capacity or gas overflow caused by too small storage tank capacity, thereby optimizing space and cost. The power and operating time of the carbon dioxide methanol production equipment are directly related to the energy storage time, ensuring that the methanol production is synchronized with the gas supply in the energy storage stage, avoiding waste of raw materials or reaction interruption. The configuration method of the present invention can accurately determine the power and capacity of the energy storage equipment and the energy release equipment, thereby ensuring that each equipment can operate efficiently and reliably; it realizes the full process optimization of the energy storage and release system from equipment parameters to operation strategy, which not only improves the energy conversion efficiency and system economy, but also enhances environmental friendliness through carbon cycle design.

[0052] Furthermore, in the energy release system, the thermochemical energy release and methanol combustion heat supply can work together or be adjusted independently: when the thermochemical energy release power is insufficient, the methanol combustion power can be increased (using redundancy). ) quickly replenish heat to ensure heating stability; conversely, when methanol reserves are insufficient, thermochemical energy release can be prioritized to enhance the system's risk resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a schematic diagram of the structure of a thermochemically coupled CO2 reduction fuel production energy storage and release system of the present invention;

[0054] Figure 2 The present invention provides a configuration method for a thermochemically coupled CO2 reduction fuel production energy storage and release system. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following is a further detailed description with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. That is, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0056] The detailed description of the embodiment of the present invention provided in the following figures is not intended to limit the scope of the claimed invention, but merely represents a selected embodiment of the present invention. All other embodiments derived by those skilled in the art based on the figures and embodiments of the present invention without inventive effort shall fall within the scope of protection of the present invention.

[0057] It should be noted that the terms "comprises", "includes" or any other variations are intended to cover non-exclusive inclusion, so that a process, element, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to the process, element, method, article or apparatus.

[0058] like Figure 1 As shown, the present invention provides an energy storage and release system for thermochemically coupled CO2 reduction to produce fuel, including two parts: an energy storage system and an energy release system.

[0059] The energy storage system includes a photovoltaic curtailment unit, a thermochemical energy storage reactor, a water electrolyzer, a carbon dioxide storage tank A, a hydrogen storage tank, an oxygen storage tank, a carbon dioxide-to-methanol plant, and a methanol storage tank. The photovoltaic curtailment unit is electrically connected to the thermochemical energy storage reactor and the water electrolyzer to provide power to these two systems. The outlet of the thermochemical energy storage reactor is connected to the inlet pipeline of carbon dioxide storage tank A. The hydrogen outlet of the water electrolyzer is connected to the inlet pipeline of the hydrogen storage tank, and the oxygen outlet of the water electrolyzer is connected to the inlet pipeline of the oxygen storage tank. The outlet pipelines of carbon dioxide storage tank A and the hydrogen storage tank are respectively connected to the reaction gas inlet of the carbon dioxide-to-methanol plant. The product outlet of the carbon dioxide-to-methanol plant is connected to the inlet pipeline of the methanol storage tank. The energy release system includes a methanol combustion heating plant, carbon dioxide storage tank B, and a thermochemical energy release reactor, all connected in sequence. The methanol combustion heating plant and the thermochemical energy release reactor are used to release energy and provide heat. The fuel inlet of the methanol combustion heating equipment is connected to the outlet pipeline of the methanol storage tank, and the combustion air inlet of the methanol combustion heating equipment is connected to the outlet pipeline of the oxygen storage tank.

[0060] During the energy storage process, the photovoltaic curtailment unit provides power to the thermochemical energy storage reactor and water electrolyzer. The thermochemical energy storage reactor undergoes the CaCO₃-CaO+CO₂ energy storage reaction, with the generated carbon dioxide being piped into carbon dioxide storage tank A for storage. The water electrolyzer undergoes an electrolysis reaction, with the generated hydrogen and oxygen being piped into the hydrogen and oxygen storage tanks, respectively, for storage. Carbon dioxide storage tank A and the hydrogen storage tank provide reaction gases to the carbon dioxide-to-methanol plant, where methanol is synthesized. The resulting methanol is piped into the methanol storage tank for storage.

[0061] During the energy release process, the methanol and oxygen storage tanks provide reaction gases to the methanol combustion and heating equipment. Methanol is burned in the equipment, and the resulting carbon dioxide is piped into carbon dioxide storage tank B for storage and heat. Carbon dioxide storage tank B provides reaction gases to the thermochemical energy release reactor, where the energy release reaction (CaO + CO2 – CaCO3) occurs, providing heat.

[0062] The present invention combines a thermochemical heat storage and release system with methanol combustion for heating, ensuring reliable heating through dual heat source complementary heating. This achieves efficient coupling of energy storage and fuel preparation, improving energy utilization efficiency. It utilizes abandoned photovoltaic power for thermochemical energy storage reactions and electrolytic hydrogen and oxygen production, achieving efficient utilization of abandoned photovoltaic power and avoiding energy waste. It converts carbon dioxide and hydrogen into methanol for storage, realizing resource utilization of carbon dioxide and reducing greenhouse gas emissions. Combusting methanol provides heat for thermochemical energy release reactions, achieving an efficient cycle of energy storage and release, and improving energy storage density and storage time. The entire system process requires no external energy input, and only utilizes abandoned photovoltaic power to achieve energy storage and fuel preparation, reducing energy consumption and costs.

[0063] like Figure 2 As shown, the present invention also provides a configuration method of the system, which is as follows:

[0064] Step 1: Based on historical data and on-site surveys, the average PV curtailment power Pq, the new heating demand load Wt, and the average outdoor daily ambient temperature Ta are obtained based on time, as shown in Table 1.

[0065] Table 1

[0066]

[0067] Based on basic data, the requirements for thermochemical energy storage and release systems, water electrolysis hydrogen production systems, and CO2 reduction fuel production systems are configured and analyzed, including:

[0068] 1. Determine the rated power and storage time of the thermochemical energy storage reactor and the CO2-to-methanol equipment. The reaction occurring in the thermochemical energy storage reactor is: CaCO3—CaO+CO2ΔH=178kJ / mol

[0069] Assuming that 1 mol of CO2 is generated, 178 kJ = 0.05 kWh of energy is consumed.

[0070] The energy consumed by the corresponding water electrolysis system is as follows:

[0071] Assume that a water electrolysis system consumes 5 kWh to produce 1 standard cubic meter of hydrogen. One standard cubic meter of hydrogen is equal to 89.3 grams. 22.4 liters of hydrogen is 1 mol of hydrogen, which is equal to 2 grams. (1000 / 22.4 * 2 = 89.3 grams.) Therefore, the electricity required to produce 3 mol of H2 is: 6 grams / 89.3 grams * 5 kWh = 0.34 kWh.

[0072] The energy consumed by the corresponding CO2 methanol production equipment is as follows:

[0073] CO2(g)+3H2(g)=CH3OH+H2O△H=-50KJ / mol

[0074] This reaction is an exothermic reaction, so the energy consumed by the reaction is not considered for the time being.

[0075] Therefore, in the abandoned power recovery stage, the rated power P of the thermochemical energy storage reactor is r With water electrolyzer rated power P H2 Almost satisfies the following relationship: 7P r =P H2 .

[0076] Obtain the average photovoltaic power curtailment per hour Pq from Table 1. So far, the average daily photovoltaic power curtailment Pt is calculated based on the average photovoltaic power curtailment per hour, and the rated power of the water electrolyzer P is obtained. H2 and the rated power P of the thermochemical energy storage reactor r , satisfying the following relationship: Pt≥P r +P H2 .

[0077] Specifically, Pt = (Pq0 + Pq1 + Pq2 + ... + Pq24) / 24h

[0078] In the heat storage stage, it is necessary to satisfy Pt≥Pr+PH2, and because 7P r =P H2 , so Pt≥8Pr, so Pr and P can be calculated respectively H2 .

[0079] According to the average daily photovoltaic power curtailment Pt, the storage time hc of the thermochemical energy storage reactor and the operating time h of the electrolyzer are determined. H2 Among them, hc is the total time that Pq is in the range of 0.6Pt to Pt, h H2 It is the total time that Pq is in the range of 0.8Pt to Pt.

[0080] According to the gas demand of the thermochemical energy storage reactor and CO2 methanol production equipment, the volumes of the CO2 storage tank, H2 storage tank, O2 storage tank and methanol storage tank (VCO2, VH2, VO2, Vm) are determined;

[0081] Determine the rated power Pf and operating time hf of the carbon dioxide to methanol equipment.

[0082] Where hf = hc, Pf = P H2 / 3.

[0083] 2. Determine the heating power and duration of the thermochemical energy release reactor and methanol combustion heating equipment:

[0084] Based on the average load of the new heating demand Wt and the average daily outdoor ambient temperature Ta, the total heating capacity W1 of the thermochemical energy release reactor and the methanol combustion heating equipment is determined, satisfying W1 = Wt*24.

[0085] The reaction in the thermochemical energy release reactor: CaO + CO2 - CaCO3 ΔH = 178 kJ / mol

[0086] 1 mol of CO2 participating in the reaction will release 178kJ=0.05kWh of energy.

[0087] CH3OH+3 / 2O2—CO2+2H2OΔH=726.51kJ / mol

[0088] 1 mol of CH3OH participating in the reaction will release 726.51kJ=0.20kWh of energy.

[0089] Therefore, the rated power P of the thermochemical energy release reactor is r1 Methanol combustion heating equipment P m Almost satisfies the following relationship: 4P r1 =P m .

[0090] In order to ensure that CaO fully reacts, the power matching between the thermochemical energy release reactor and the methanol combustion heating equipment should have a certain degree of redundancy. The redundancy

[0091] According to the temporal variation pattern of the average load of the new heating demand, the optimal heating time ho of the system is determined according to the principle of economic optimization, thereby calculating the total heating power P1 of the thermochemical energy release reactor and the methanol combustion heating equipment.

[0092] P1=W1 / ho;

[0093] Among them, ho is the total time that Wt is in the range of 0.7W1 to W1.

[0094] According to P1, we can get P r1 and P m The specific formula is as follows:

[0095] P1=P r1 +P m , P m =4P r1 *φ, where redundancy 1≤φ≤2.

[0096] The redundancy setting allows the system to adjust flexibly under different loads and improve stability.

[0097] This invention integrates multiple energy storage methods, combining thermochemical and chemical fuel storage to meet different needs, such as heat supply and power storage. This multi-energy complementary design may improve the overall utilization rate of the system and reduce the limitations of a single energy storage method.

[0098] We also need to consider practical application scenarios. For example, in areas with abundant solar energy but insufficient grid capacity, waste electricity can be used to store energy while also meeting heating needs. This solves the problem of waste electricity and provides thermal energy, killing two birds with one stone. Regarding environmental protection, CO2 is converted into methanol, reducing emissions. Simultaneously, the CO2 generated by methanol combustion is recycled, forming a closed loop and reducing the carbon footprint.

[0099] In terms of economic efficiency, the configuration method determines the heating duration based on the principle of economic optimization, which may optimize operating costs and improve the feasibility of the system. At the same time, the recycling of materials, such as calcium carbonate and calcium oxide, reduces consumable costs and improves the economic efficiency of the system.

[0100] System flexibility may also be considered, such as adjusting operating hours based on changes in photovoltaic power curtailment, adapting to varying weather conditions and electricity demand, and improving system reliability and adaptability. Furthermore, methanol, as an energy storage medium, is easy to store and transport, suitable for long-distance transmission, and may play a role in regional energy systems.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A thermochemically coupled CO2 reduction fuel production energy storage and release system, characterized in that: Including energy storage system and energy release system; The energy storage system includes a photovoltaic power curtailment unit, a thermochemical energy storage reactor, a water electrolyzer, a carbon dioxide storage tank A, a hydrogen storage tank, an oxygen storage tank, a carbon dioxide to methanol device, and a methanol storage tank; The photovoltaic power abandonment unit is connected to the thermochemical energy storage reactor and the water electrolyzer to provide power to the thermochemical energy storage reactor and the water electrolyzer; The thermochemical energy storage reactor is connected to the carbon dioxide storage tank A, and the water electrolyzer is connected to the hydrogen storage tank and the oxygen storage tank respectively; the carbon dioxide storage tank A and the hydrogen storage tank are respectively connected to the carbon dioxide to methanol equipment; the carbon dioxide to methanol equipment is connected to the methanol storage tank; The energy release system includes a methanol combustion heating device, a carbon dioxide storage tank B and a thermochemical energy release reactor connected in sequence. The methanol combustion heating device and the thermochemical energy release reactor are used for energy release and heating; The methanol combustion heating equipment is connected to the methanol storage tank and the oxygen storage tank respectively.

2. The energy storage and release system for thermochemically coupled CO2 reduction to fuel according to claim 1, characterized in that: The thermochemical energy storage reactor is filled with calcium carbonate material, and the thermochemical energy release reactor is filled with calcium oxide material.

3. The energy storage and release system for thermochemically coupled CO2 reduction to fuel according to claim 1, characterized in that: The methanol combustion heating equipment is also connected to the water electrolyzer to supply water to the water electrolyzer.

4. The operating method of the energy storage and release system for thermochemically coupled CO2 reduction to fuel according to any one of claims 1 to 3, characterized in that: The following steps are involved: The thermochemical energy storage reactor uses the abandoned photovoltaic power to perform energy storage reaction, generating carbon dioxide, which is stored in the carbon dioxide storage tank A; The water electrolyzer uses the abandoned photovoltaic power to perform electrolysis reactions to generate hydrogen and oxygen, which are stored in hydrogen storage tanks and oxygen storage tanks respectively; The carbon dioxide storage tank A and the hydrogen storage tank provide reaction gas for the carbon dioxide to methanol equipment to generate methanol, which is stored in the methanol storage tank; The methanol storage tank and oxygen storage tank provide reaction gas for the methanol combustion heating equipment to generate carbon dioxide, which is stored in the carbon dioxide storage tank B and provides heat at the same time; The carbon dioxide storage tank B provides reaction gas to the thermochemical energy release reactor, performs energy release reaction in the thermochemical energy release reactor, and provides heat.

5. The operating method of the thermochemically coupled CO2 reduction fuel production energy storage and release system according to claim 4, characterized in that: Calcium oxide is generated in the thermochemical energy storage reactor and transferred to the thermochemical energy release reactor; Calcium carbonate is generated in the thermochemical energy release reactor and transferred to the thermochemical energy storage reactor; During the reaction in the methanol combustion heating equipment, the generated water is circulated to the water electrolyzer.

6. A configuration method for a thermochemically coupled CO2 reduction fuel energy storage and release system according to any one of claims 1 to 3, characterized in that: It includes the following two parts: Configure the energy storage system: Average photovoltaic power curtailment, new heating demand load, and average outdoor daily ambient temperature established over time; Determine the relationship between the rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer based on the energy consumption in the thermochemical energy storage reactor and the water electrolyzer; The average daily photovoltaic power curtailment power is calculated based on the average photovoltaic power curtailment power established with time as the axis; The rated power of the water electrolyzer and the rated power of the thermochemical energy storage reactor are obtained based on the relationship between the rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer and the average daily photovoltaic power abandonment; Determine the storage time of the thermochemical energy storage reactor and the operating time of the electrolyzer based on the average daily photovoltaic power curtailment. Determine the volumes of CO2 storage tanks, H2 storage tanks, O2 storage tanks, and methanol storage tanks based on the gas requirements of the thermochemical energy storage reactor and CO2 to methanol equipment; Determine the power and operating time of the CO2-to-methanol equipment based on the energy storage time of the thermochemical energy storage reactor and the operating time of the electrolyzer; Configure the energy release system: Determine the total heating load of the thermochemical energy release reactor and methanol combustion heating equipment based on the average load of the new heating demand and the average daily outdoor ambient temperature; Determine the relationship between the rated power of the thermochemical energy release reactor and the rated power of the methanol combustion heating equipment; Based on the temporal variation of the average load of the newly increased heating demand and the principle of economic optimization, the optimal heating duration of the system is determined. Based on the optimal heating duration and heating load, the total heating power of the thermochemical energy release reactor and the methanol combustion heating equipment is calculated. The rated power of the thermochemical energy release reactor and the rated power of the methanol combustion heating equipment are calculated based on the heating power.

7. The configuration method of the thermochemically coupled CO2 reduction fuel production energy storage and release system according to claim 6, characterized in that: The rated power of the thermochemical energy storage reactor and the rated power of the water electrolyzer satisfy the following relationship: <h2 style=";text-align:left;direction:ltr">P<h2 style=";text-align:left;direction:ltr"> H2 <h2 style=";text-align:left;direction:ltr"> =7P<h2 style=";text-align:left;direction:ltr"> r <h2 style=";text-align:left;direction:ltr"> ; Among them, P r is the rated power of the thermochemical energy storage reactor, P H2 Rated power of the water electrolyzer.

8. The configuration method of the thermochemically coupled CO2 reduction fuel production energy storage and release system according to claim 6, characterized in that: The storage time of the thermochemical energy storage reactor is hc, and the operation time of the electrolyzer is h H2 ; hc is the total time that Pq is in the range of 0.6Pt to Pt, h H2 is the total time that Pq is in the range of 0.8Pt to Pt; Pq is the average photovoltaic power curtailment power established based on time, and Pt is the average daily photovoltaic power curtailment power; The rated power of the carbon dioxide to methanol equipment is Pf, the operating time is hf, and the calculation expression is: hf=hc,Pf=P H2 3 / ;P H2 Rated power of the water electrolyzer.

9. The configuration method of the energy storage and release system for thermochemically coupled CO2 reduction to fuel according to claim 6, characterized in that: The rated power of the thermochemical energy release reactor is P r1 The rated power of the methanol combustion heating equipment is P m , the relationship between the two is: The redundancy 10. The configuration method of the energy storage and release system for thermochemically coupled CO2 reduction to fuel according to claim 9, characterized in that: The total heating power of the thermochemical energy release reactor and the methanol combustion heating equipment is calculated based on the optimal heating time ho and the heating load W1. The expression is: P1 = W1 / ho; Among them, ho is the optimal heating time, W1 is the heating load, and P1 is the total heating power of the thermochemical energy release reactor and methanol combustion heating equipment; The rated power P of the thermochemical energy release reactor is calculated based on the heating power P1. r1 Methanol combustion heating equipment P m , based on: P1=P r1 +P m .

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